1. Field of Invention
The present invention relates to an optical fiber sensing technology, and more particularly to a new optical fiber temperature sensor.
2. Description of Related Arts
Optical fiber temperature sensors have a wide range of applications. They use optical fiber as the optical path for separating the probe from the instrument so as to improve the environmental adaptability. The sensor can work under conditions of strong electromagnetic interference, high voltage and electrical power transmission without using any additional wire. Currently, fluorescent sensors, birefringent crystal sensors and semiconductor sensors are the major successful optical fiber temperature sensors. Most of the existing optical fiber temperature sensors are mostly based on the principle of the spectral analysis, such as the fiber grating mentioned in the reference [1] of Fiber Bragg Grating Temperature Sensor with Controllable Sensitivity; Jaehoon Jung, Hui Nam, Byoungho Lee, Jae Oh Byun, and Nam Seong Kim; Applied Optics, Vol. 38, no 13, pp. 2752-2754; the fiber Fabry-Perot etalon mentioned in the reference [2] of Fabry-Perot Fiber-Optic Temperature Sensor; Lewis Research Center, Cleveland, Ohio NASA, Tech Briefs; Friday, Jan. 1, 1999; semiconductor absorption sensor mentioned in the reference [3] of Optical Fiber Temperature Sensor Applying Spectral Analysis; Sensor Technology, Vol. 20, Issue 11; 2001. They all require spectral analysis, and have complex manufacturing process and high cost.